Astronomers estimate that the Big Bang occurred between 10 and 20 billion years ago.
They estimate the age of the Universe in two ways: (a) by looking for the oldest stars; and (b) by measuring the rate of expansion of the Universe and extrapolating back to the Big Bang..
Astronomers have derived two different measurements of the age of the universe: a measurement based on direct observations of an early state of the universe, which indicate an age of 13.787\xb10.020 billion years as interpreted with the Lambda-CDM concordance model as of 2021; and a measurement based on the observations .
The Cosmic Calendar is a scale in which the 13.7 billion year lifetime of the universe is mapped onto a single year.
This image helps to put cosmology, evolution, and written history in context.
At this scale the Big Bang took place on January 1 at midnight, and the current time is mapped to December 31 at midnight..
These models estimate the universe to be 13.8 billion years in age, based on the big-bang expanding universe concept.
My research proposes a model that determines the universe's age to be 26.7 billion years, which accounts for the JWST's “impossible early galaxy” observations..
The Big Bang was the moment 13.8 billion years ago when the universe began as a tiny, dense, fireball that exploded.
Most astronomers use the Big Bang theory to explain how the universe began.
But what caused this explosion in the first place is still a mystery..
The images can be interpreted to indicate that the universe is 13.7 billion years old (within one percent error), and are very consistent with the Lambda-CDM model and the density fluctuations predicted by inflation.
Cosmic microwave background as measured by the Cosmic Background Imager experiment.
Contemporary Biblical cosmology reflects the same view of a flat, circular Earth swimming on water and overarched by the solid vault of the firmament to which are fastened the stars. 6th–4th century BCE – Greek philosophers, as early as Anaximander, introduce the idea of multiple or even infinite universes.
The chronology of the universe describes the history and future of the universe according to Big Bang cosmology.
Research published in 2015 estimates the earliest stages of the universe's existence as taking place 13.8 billion years ago, with an uncertainty of around 21 million years at the 68% confidence level.
This timeline of cosmological theories and discoveries is a chronological record of the development of humanity's understanding of the cosmos over the last two-plus millennia.
Modern cosmological ideas follow the development of the scientific discipline of physical cosmology .
